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By P. W. Udo Graefe

"An interactive computer model of a dragline, windrow and spoil pile has been developed for modelling oil sands mining operations. The model is to be used in conj unction with models of other oil sands mining equipment, such as bucket-wheel excavators and reclaimers, conveyors, hoppers, bins, trucks and shovels, to study mining operations on a minute-by-minute basis. From the orebody description and mining selectivity, layers of ore and reject are determined and mined by the dragline. Reject is dumped on the pit floor; ore is either dumped on a windrow for later removal by a bucket-wheel reclaimer or directly dumped into a hopper feeding a conveyor. The model allows for the presence of pads as a dragline base, key cuts and a number of interruptions to the mining operation such as shift changes, boom checks, engineering services, repairs, delays, preventative maintenance, etc. A CRT display keeps the model operator informed about equipment status and performance. The model operator can direct the course of the simulation by issuing commands to the model at any time during the simulation.IntroductionThis paper describes an interactive computer model of a dragline, windrow and spoil pile. The model was designed by the author based on information and specifications provided by Canstar Oil Sands Ltd. The model design was implemented and tested on Petro-Canda's IBM computer system by DMR and Associates Ltd. of Calgary, Alberta.The model was designed to form three components of an oil sands mining operations model, described in reference I. Figure 1 shows the interaction of those components with the remainder of the oil sands mining model.An ""Ore/Waste Body"" data base provides information to the dragline model about the location and composition of or e and waste in the mine. The dragline model is used to simulate mining this ore/waste body, to build up spoil piles for center reject (waste) and to dump ore onto windrows or hoppers (situated over conveyors) to deliver the ore to the extraction plant. The windrow model component provides a data base which will be used by a model of a bucket-wheel reclaimer which simulates the loading of ore from the windrow on to a conveyor via a bridge."

Jan 1, 1982

By S-E. Vandat

The goal of this work was to select an appropriate electrode for dummy load of diesel engine in fully salt-water in the DESA factory. The electrochemical corrosion rate of general structural steel, commercial pure aluminum and cathode copper calculated as weighting, volumetric and commercial in fully salt-water by city power. After several tests and then applying the fuzzy logic method, it was determined that general structural steel is the best selection for this purpose.

Jan 1, 2005

By D. D. Hogarth

"Edward Haycock, Engineer and Public Contractor Edward Haycock was born in Shrewsbury, England, June 14, 1813. His father was John Haycock, a timber merchant and soap manufacturer, residing at Swan Hill Court, Shrewsbury, and his mother Esther was the daughter of William Hilton of Hempstead, Hertfordshire. Edward's paternal grandfather, John Hiram Haycock, was the first of a line of architects that ""changed the face of Shrewsbury"" and ""provided some of the best examples of typical Victorian architecture in Shropshire""(1). Nothing is known of Edward's early life or education, although it appears that he made no attempt to follow this artistic trend. In 1833, Edward immigrated to Canada. The following year, he married Mary Butler, daughter of Johnson Butler, a Lieutenant-Colonel in the Lincoln Militia during the War of 1812. Mrs. Haycock, as co-heiress of Johnson Butler's estate, was assigned 600 choice acres of farmland in Brooke Township near present-day Sarnia. This alone would have guaranteed a tidy income, but the Haycocks soon disposed of this land, the last lots being sold in May 1840. Instead, Haycock turned his hand to engineering and, for a number of years, was employed by the Great Western Railway first in Woodstock and later in Hamilton. He then moved to Port Hope, tried farming, worked in the engineering office of the Port Hope, Lindsay and Beaverton Railway Company, and later constructed a portion of this railway(2). During his stay in Port Hope, Haycock met his future partners Ralph Jones, a contractor, and Thomas Curtis Clarke, chief engineer with the P.H.L. and B. Railway Company. The alliance was styled Jones, Haycock and Company and their most successful venture was the construction of the Government Buildings in Ottawa. This work was the crowning achievement of Haycock's career and, no doubt, his proudest moment was at 11:30 a.m., April 2, 1860, when his daughter Mary Emily, then a little girl of 4, with a special silver trowel ceremoniously laid the first stone. Of special interest in this project were the quarrying operations, which introduced Haycock to the art and difficulties of mining as well as to the potential returns of mines. Sandstone, for facing, was drawn from four quarries, 10 to 12 miles from the Departmental Buildings. Haycock seems to have been in charge of these operations, which in the early stages involved an average labour force of 86 men and 43 teams. However, by 1861, quarrying had declined in importance and the contractors were able to concentrate whole-heartedly on the construction site."

Jan 1, 1999

By Yang Shuxin, Guo Qiliang, He Ping, Lu Lizhi, Yao Rui

"We combined stepwise regression and constrained regression statistical method to obtain the best boundary conditions for the calculation of in-situ stress field in Wushaoling tunnel using finite element method. Our numerical results reveal that: the main geologic factors contributing to the initial background stress are gravity and tectonics; the principal stress values would drop in fault zones; the angle between the maximal horizontal stress and the axis of Wushaoling tunnel is acute; Wushaoling tunnel tends to become stable when this tunnel has 2:1 ratio of the height to its width; the possibility of rock-burst exists under high stress.INTRODUCTIONStress state of engineering region is an important factor affecting the stability of project. Geological disasters in the project area are closely related to their stress environment. Wushaoling tunnel which is 20,050 meters long, lying along Lanzhou-Wuwei segment of Lan-Xin Railway in China, is the key project of Lan-Wu double-track railway. The region surrounding this tunnel is under a high stress environment. Accurate identification of the stress environment of the engineering area and the interaction between geomaterials and geotechnical engineering construction holds significant scientific and practical value for engineering design, construction, and operation.Many scholars explored and discussed the present-day tectonic stress through investigations of tectonic evolution history (Ding, & Lu, 1986), crustal deformation (Zoback, 1992), focal mechanisms (Yang et al., 2003, Xie, Cui, & Zhao, 2004), and so forth. However, the above methods would only provide the approximate direction of the principal stress in a broad region, and could not give the absolute stress values. In-situ stress measurement is one of the primary means to directly gauge the current crustal stress. However, in-situ stress measurement can only be applied in small number limited by measurement conditions."

Jan 1, 2015

By M. W. Wadsley

"Physical and chemical property models are widely used in process engineering. There exist, in the published literature, completely empirical models of ''thermodynamic properties"", that is, property models that are not consistent with the laws of thermodynamics. There also exist property models that purport to be thermodynamically consistent but are flawed in their implementation. There are also published property models that are consistent with the laws of thermodynamics but that do not reproduce property values with an acceptable accuracy. A practicing engineer might be asked to assess very different property models for which there are a variety of claims. This paper discusses features of thermodynamic and empirical property models that may assist in their practical evaluation and implementation."

Jan 1, 2005

By H. C. M. Gordon

IT is essential to the success of any mining op::ration that the roadways through which the material wrought and ocher materials and supplies are to be transported should be kept in such condition that this transportation cart be effected rapidly and without difficulty. The longer the roadway and the greater the tonnage to be taken over it, the more necessary it becomes chat the construction and maintenance of the road be such chat traffic delays can be reduced co a minimum. le is proposed co deal with the development and construction of roadways serving longwall operations and, since a recreating system of longwall is worked, as a rule, only where roadways driven in the solid coal can be readily maintained, the discussion will be confined co advancing longwall roads which are driven through areas from which the coal seam has been totally extracted. In order to construct a roadway through extracted ground in such a manner that it will remain in a state of reasonably good repair without undue maintenance, it is necessary chat everything possible be done to bring the overlying strata co a state of equilibrium as quickly as this can be effected, and the operations should be so planned that future workings will not disturb the equilibrium so set up more than can be avoided. Obviously, the readiest way to obtain a stable roadway is to develop it by tunnelling through a settled waste. However, this cannot always be done, as some of the roadways must be developed and constructed as the walls progress, but level or lateral cut-offs can be constructed in this manner. Main-slope roads can be developed in a similar manner after the coal has been extracted and a waste formed for at !east five hundred feet on either side of the line of the permanent roadway from temporary subsidiary roads developed for this purpose along one or other of the flanks of the waste to be formed. This interval must be obtained in order chat the lacer extraction of the seam will not set up movements in the waste immediately overlying or adjacent to the constructed roadway, thus upsetting the equilibrium of the strata and distorting the road.

Jan 1, 1940

By G. Deschênes

Located in North West Tanzania, Buzwagi is an underground narrow-vein gold mine owned by Barrick Gold. The plant was commissioned in 2000. The reserves are estimated to be more than 25 years. The ore, containing gold, silver and copper mineralization in sulphides, is processed at 3,300 tpd. This paper presents the results of an investigation to determine the performance of an ammonia-cyanide leaching approach to recover gold from two samples. Coarse gold was recovered by gravity prior to leaching. The gravity tailings had the following composition; 1.97 g/t Au and 0.31% copper for the medium cyanide soluble copper (MCSC) sample and 2.80 g/t Au and 0.53% Cu for the high cyanide soluble copper (HCSC) sample. Experiments were conducted for 72 hours in stirred tank reactors with monitoring and control of parameters. The straight cyanidation produced gold extractions of 76.1% for the MCSC sample and 84.6% for the HCSC sample. Associated cyanide additions were 6.1 kg/t and 11.5 kg/t respectively. The gold extraction of the MCSC sample was improved to 88.8% using 350 ppm NaCN and 700 ppm ammonia. The associated cyanide and ammonia additions were 2.5 kg/t and 1.7 kg/t respectively. For the HCSC sample, 82.5% gold extraction was obtained using 500 ppm NaCN and 600 ppm ammonia. The cyanide addition and ammonia additions were reduced to 3.8 kg/t and 1.0 kg/t respectively. No significant decrease in gold extraction was noticed when the cyanide and ammonia were reduced to 150 ppm and 500 ppm respectively. In the presence of ammonia, a significant amount of cyanide was oxidized to cyanate by the cupric ion. In the absence of ammonia, the formation of copper cyanide was the predominant reaction responsible for consumption of cyanide.

Jan 1, 2012

By Karl Hoover, Cassandra Spence, Brent Bachewich, Jaakko Levanaho

"Since year 2000 the gold recovery into copper concentrate at Hudson Bay Mining and Smelting has reduced considerably during the summer months. This initiated a testwork program in the fall 2003 to find reasons and solutions for such change. During the testwork mineralogical factors, water quality effects and different reagents were evaluated. The reason for the lower recovery appeared to be the sensitivity of some collectors to pulp temperature. As a result of the work different collectors are being used in the mill in the summer than in the winter. A modification to the water system was also made to provide cooler water to the mill in the summer months.INTRODUCTIONHudson Bay Mining and Smelting (HBMS) is located in Northern Manitoba, just on the border of Manitoba and Saskatchewan. The complex consist of four different mines, Callinan, Trout Lake, Konuto Lake and 777 mine including copper smelter and zinc hydrometallurgical plants producing metallic copper and zinc. Gold is a very important byproduct providing about 30% of the mine revenue. In early 1990s when the company was facing declining ore reserves and was starting to gradually close down the operations, the 777’th exploration drill hole discovered a new orebody, which initiated a $0.5 billion expansion program. The main projects were a new 777 hoist with underground development and a new zinc cell house. About $30 million was used to increase the mill throughput to the present 2.27 million tonnes or 2.5 million short tons per year. The expansion programs were finished by the end of the year 2003.Historically the gold recovery at HBMS has varied between 60 and 70%. The recovery has been somewhat lower during the summer months. Gold recovery improvement projects were conducted throughout the 1990s, but were not focused on the seasonal gold recovery variance. However, since 2000, when the water system modifications to meet the increased water demand were completed, the gold recovery during the summer has been much lower than in the past. In August 2003 gold recovery fell below 30%, which initiated a metallurgical research program to discover the reasons behind the low gold recovery in the summer."

Jan 1, 2005

By J. C. Johnson

Underhand mining with cemented mill tailings for backfill has proven to be a safe and effective alternative to conventional overhand mining for rockburst prone mines. The ability of the cemented sandfill to survive a rockburst shock wave without failing has been observed at mines in the Coeur d?Alene Mining District many times in the last twenty years. To better understand the dynamic loading of this commonly used support material the National Institute for Occupational Safety and Health (NIOSH) performed laboratory experiments using a split Hopkinson Pressure Bar (SHPB) to quantify the maximum stress and energy absorption of cemented mill tailings from the Galena mine. Cylindrically shaped cemented backfill specimens aged 28 days were placed in the split Hopkinson pressure bar testing apparatus and a dynamic load was applied. The measured peak dynamic compressive strength of the cemented sandfill was 10.6 MPa (1540 psi) and is approximately twice the static unconfined compressive strength (UCS) of 5.5 MPa (800 psi). These test data showed about 95% of the initial energy was reflected away from the backfill and only 5% of the energy was absorbed. This may help to explain why backfilled stopes could withstand seismic events up to 3.5 Richter magnitude (Ml). When a compressive rockburst wave impacts a stope a large amount of the stress and energy is reflected away. The reflected wave is a tensile wave which creates tensile cracks and spalling in the entire wall of the stope. The backfill supports the damaged wall rock and holds it in place. Some of the stress and energy of the rockburst is transmitted into the backfill and because the backfill is being dynamically loaded it has a strength that is twice its static value and absorbs a substantial amount of rockburst energy. Although mining in deep underground mines is an extremely hazardous occupation, the use of underhand mining with cemented backfill for static and dynamic ground control increases the safety of the workers.

May 1, 2007

By Amin Saravari, Jamal Jafari, Abbas Sam

"The fourth concentrate production plant includes the comminution systems and the medium-low intensity magnetic separators (LIMS). Based on different conditions, two types of materials are fed into the plant. Type A: 70% of mine ore and 30% of reject materials from magnetite plant and type B: 100% of mine ore. The goal of the present study was to increase the iron grade and the blain number with low sulfur content in final concentrate as the pellet feed. An appropriate pellet feed should have more than 67% of iron, less than 0.1% of sulfur and a Blain number of more than 1800 cm2/g. The Fe, S and Blain no. amounts for the present concentrate are 66.6%, 0.95%, and 500 cm2/g (feed type:A) and 67.8%, 2.3%, and 450 cm2/g (feed type: B), respectively. In this research, the plant improvement efficiency was evaluated by changing the feed particle size distribution and using the flotation system. Laboratory experiments were designed based on the three circuits:1) LIMS (Low Intensity Grinding Rolls) feed grinding-LIMS test-flotation test2) LIMS feed grinding-flotation test-LIMS test3) LIMS concentrate grinding-flotation testThe best results were obtained using the first circuit at the LIMS feed size (d80) of 132 ?m. The processing results using the circuit no. 1 (feed type: A), showed a LIMS concentrate with 69.8% of Fe and 0.36% of sulfur. In this case, the final concentrate (after flotation) with Fe grade of 70.3%, sulfur content of 0.07% and Blain no. of 1571 cm2/g were obtained. In case of the feed type of B, the LIMS concentrate with Fe grade of 68.7%, and sulfur grade of 1.6% was achieved. Also, the Fe and sulfur contents were 69.3%, and 0.4% respectively with a Blain number of 1112 cm2/g. According to the obtained results, it was suggested that a LIMS feed comminution along with a LIMS and flotation systems are necessary to achieve an appropriate iron and sulfur grades with an acceptable blain number. To reach a concentrate Blain number as a pelletizing feed, a High Pressure Grinding Rolls (HPGR) system at the end of the processing line was recommended."

Jan 1, 2016

By D. W. McDonald, N. A. Duke, R. L. Hauser

"Abstract- The NERCO Con Mine is situated in the amphibolite facies aureole of the Western Plutonic Complex overprinting the Yellowknife Greenstone Belt. Metamorphic grade of the upright monoclinal basaltic succession decreases from hornblende-amphibolite facies along the border of the batholith to greenschist facies. Metamorphic isograds, subparalleling the faulted margin of the batholith, transect volcanic stratigraphy and coincide with major gold­ bearing shears.Gold mineralization is confined to north-striking, west-dipping shear zones where hanging­ wall amphibolite facies mineral assemblages retrogress to chlorite-carbonate-sericite-sulfide bearing schists hosting multiple generations of quartz-ankerite veins. The gold-producing portions of the Con and Campbell Shears occur where these structures transect an east trending thermal corridor. The corridor is defined by granitic plugs and a number of related breccia bodies, that can be traced outwards from the batholith across the greenstone belt.Prograde reactions of greenstone during amphibolitization effectively liberate fluids that partition metals. With retrograde reactions at shear zones, gold is precipitated with quartz due to the destabilization of sulfide and arsenic complexes. The coupling of regional prograde metamorphic and restricted retrograde metasomatic overprints suggest mineralization is temporally related to emplacement of the Western Plutonic Complex. Economic gold concentrations within the intrusive corridor indicates enhanced metamorphic overprint of hornfelsed greenstones enveloping satellite intru sives peripheral to the main batholith."

Jan 1, 1993

By W. Beres

Many non-commercial operators are currently faced with the need to operate fleets of legacy gas turbine engines. How long such engines can be kept in service safely, without replacing a significant portion of their aging structural components, has become a growing concern to engine life-cycle managers, due to uncertainties in the remaining lives of critical components of these engines. This paper describes the application of the damage tolerance methodology to predict safe inspection intervals (SII) for critical components of gas turbine engines, using components of a turboprop engine for a transport aircraft as examples. High temperature components of this engine are made of advanced aerospace alloys. The methods of predicting three-dimensional fatigue crack growth at the critical location of turbine discs and spacers using both commercial and in-house developed algorithms are presented. Sensitivity analyses are performed to determine the effect of variations in material parameters on the predicted safe inspection intervals. In addition, spin rig tests performed for both turbine discs and spacers are described. Finally, crack growth rates predicted by numerical analyses are compared to those obtained from spin rig testing and the damage tolerance of the turbine components is assessed.

Jan 1, 2015

The negative effects of pyrite and pyrrhotite on thiosulfate gold leaching have been investigated. Possible remedies to reduce some problems are discussed. In a gold bearing pure silicate ore, 92% of gold could be extracted within 3 hours using a solution containing 0.2 mol/L ammonium thiosulfate, 0.9 mol/L ammonia, 30 - 300 ppm copper sulfate and 8.6 ppm dissolved oxygen at pH 10.26. The thiosulfate consumption was 7.1 kg/t under these conditions and could be further reduced to 3.5 kg/t by decreasing the dissolved oxygen to 0.3 ppm. Addition of 16% pyrrhotite or pyrite into the silicate slurry led to a decrease in gold extraction by 2% or 9% respectively and an increase of thiosulfate consumption by 11 kg/t or12.8 kg/t respectively in three hours. Several adjustments, such as increasing copper ion and ammonia concentration and reducing the dissolved oxygen level to 0.3 ppm resulted in increased gold extraction and lower thiosulfate consumption despite the presence of these sulfides.

Jan 1, 2005

By M. N. Pons, E. Benizri, B. Laubie, A. Bani, Université de Lorraine LRGP, P. Kidd, A. J. M. Baker

"Serpentine (i.e. ultramafic) outcrops in Europe cover more than 10,000 km2 and have a low-fertility and low-productivity, making them unattractive for traditional agriculture. In general, these areas are slowly abandoned by local farmers, affected by strong rural exodus and landscapes undergo a process of closure. However, ultramafic landscapes have the potential to provide multiple ecosystem services that can contribute to Europe’s goals towards insuring food security, production of renewable raw materials and renewable energy. Phytomining (agromining) aims at cultivating metal hyperaccumulator plants that are able to accumulate Ni and other strategic elements from metal-rich soils and transport them to the shoots (>1%), which can then be harvested as a bio-ore. Such metal-rich biomass can be used to recover highly valuable metals, e.g. nickel (Ni) and also to produce energy (heat, electricity). Nickel agromining can thus offer an eco-efficient alternative to classical pyro- or hydrometallurgical processes without disturbing the soil cover and the geology from soils and rocks that would be considered as low grade ores or sterile material for conventional mining methods.Phytomining agroecosystems can lead to better soil resource efficiency and can offer a fully integrated, new agromining agriculture that could cover thousands of km2 in Europe, benefit local communities with a sustainable rural development and provide a wide array of ecosystem services which will need to be optimised under a life cycle assessment methodology:1. Production of bio-sourced metal products2. Production of energy biomass3. Restoration of soil fertility for conventional agriculture (Ni stress)4. Limiting Ni intake by local populations and farmers5. Use and conservation of local biodiversity (plant and soil fauna and microflora) as cultivated ecosystems6. Store carbon in cultivated soils7. Enhance pollination activity at landscape level.Nickel agromining could therefore change the economical balance in historically-disadvantaged ultramaficregions of Europe"

Jan 1, 2016

By D. Furrer, M. Dallaire

The arrival of Image analysis in the last 20 years has changed the world of quantitative metallography. Many standard measurement techniques which were previously manual can now be done with fully automated systems. This reduces subjectivity and operator fatigue and therefore enhances the quality of the statistical results. In many laboratories, Titanium Alloy microstructures continue to be evaluated by traditional methods, where quality of results is subject to operator fatigue and level of experience. Advances in Camera technology have tremendously improved image acquisition. One can often see clearly at 500x what can not be observed at 1000x, allowing for a larger area to be analyzed, without the inconveniences associated with very high magnification objectives. Powerful and versatile Image analysis software combined with a high precision motorized stage gives access to a multitude of applications, which were extremely challenging or impossible until now. Image Analysis tools such as Multilayer Grab, which reconstructs an uneven image into one plane of focus (ex. Observation at high magnification of texture resulting from etching) and Mosaic which builds an image from a number of fields of view (ex. Reconstruction of very large grains at low magnifications) expand even further the power and flexibility of IA systems. This presentation will describe how automated methods are applied to the point count method and grain size measurement. We will show how cameras and software work together to permit quantitative measurements of primary alpha and prior beta microstructures, as well as lamellar alpha plate thickness in titanium alloys.Automated and semi automated quantitative measurements of various Titanium microstrures have been assessed, using the Clemex Vision PE. Examples of the methods and steps used are presented.

Jan 1, 2006

ONE of the morning sessions at the recent Annual Meeting was devoted to a Symposium on ways and means to expedite geological investigation, and also to promote greater prospecting activity, in Canada. It will be recalled that at the 1940 Annual Meeting, held in Winnipeg, a paper(l) prepared by Dr. G. A. Young, Chief Geologist of the Geological Survey, was presented, and was followed by a Symposium on Geological Investigations in Canada(2). On that occasion, the participants were in the main geologists, and they included the directors or other officials of each of the Provincial departments or bureaus of mines. At the Montreal meeting, the subject was discussed mainly from the point of view of the mining industry. The following pages present, in somewhat summarized form, the several contributions to that discussion.-ED. DR. J. J. O'NEILL(3), who was to have opened the Symposium, was unfortunately prevented through illness from attending the meeting. He had intended outlining the main features of his paper on The Exploitation and Conservation of Mineral Resources in a Balanced Development of Canada, presented at the last annual meeting of the Royal Society of Canada( 4). In his absence, DR.J. A. DRESSER presented a summary of the paper.

Jan 1, 1941

By Louis Frost

"1N 1951, the Dominion Steel and Coal Corporation, as part of a programme of modernization in their coal mining operations at Sydney Mines and Glace Bay, Nova Scotia, undertook the development of two large cross-measure tunnels, which were to be used for the purpose of raising the coal from the underground workings by conveyor belts direct to wash plants located on the surface.These tunnels were to reach from the surface to central loading points underground located at a depth of 600 and 900 feet, respectively. They were to be driven on a pitching gradient of 11 degrees to the horizontal, and they were to reach a length of 3,600 feet in the Sydney Mines area and 10,000 feet in the Glace Bay area.The longer tunnel, 19 feet in diameter, was driven a distance of 1,500 feet and, for domestic reasons, bas not yet been •completed. The other tunnel, in the Sydney Mines area, 18 feet in diameter, is steel supported and concreted throughout its entire length. This tunnel has been completed and will be in operation at an early date.The development of this particutar tunnel posed an additional problem, as the rock through which it had to pass was considered to be water-bearing. In the sinking of Princess Colliery shafts in 1866, a great deal of water had been encountered, and it had been necessary, while sinking, to line the shaft with cast-iron tubbing through the water-bearing strata. The shaft had to be lined for a depth of 300 feet at the upper end. It was anticipated that we would meet with difficulty in driving the tunnel through this strata."

Jan 1, 1955

By Farnham. G. S.

It is difficult co know how to deal with this subject before a group having such mixed interests. The mining man is not coo concerned with the problems of alloy research. The engineer is more interested in properties of materials than how these properties can be achieved. The business man feels that scientific history and prognostication are not for him, predicting trends or possible developments in the economic field being a more than sufficient occupation. Yet the application of physical metallurgy research to industry is of importance to miner, engineer, and business man, for only through such application can the continuing existence of industries manufacturing or consuming metals be assured. History shows that hard work does not guarantee industrial survival. For instance, the Bessemer method of steel making superseded puddling operations; it, in its turn, has been largely displaced by open-hearth processing; later, steels made in electric-arc furnaces displaced open-hearth products in the quality field; and now, very specialized steels are being made in high-frequency rather than in arc furnaces. It is apparent then, if industry is co remain healthy, complacency must give way co imaginative planning, based on a thorough knowledge of production technique, a knowledge supplied by efficient research.

Jan 1, 1947

By M. Cousineau, S. Gariepy

"Current business and corporate environments push for improving metal accounting practices in smelters. The ensuing projects commonly proceed along a bottom-up approach. As such, efforts are first put on reviewing the measurement system and then on remedying the identified weaknesses. The focus is thus moved to mass/metal balance only after the measurements upgrade process has been completed. However, practice has shown that assessing the high variances related to suboptimal measurement processes is complicated without the help of statistical data reconciliation. This bottom-up approach leads to a to-do list that can not only exceed available resources but also lack prioritization in view of achieving the targeted end use. This paper describes an upgrade project done differently where all the three dimensions of the metal accounting system: hardware, software, and people were instead involved at the onset. Personnel was thus trained on data reconciliation software at the beginning of the project to make the reconciled mass balance benefits available earlier in the upgrading project. This has pinpointed the most critical measurements where accuracy and reproducibility should be improved. Overall, not only the instrumentation retrofitting process has been streamlined, but the global risk for the whole upgrading project has been significantly lowered.INTRODUCTION Mining companies are pressured to improve their production accounting practices in response to the strengthening of corporate requirements for timely and accurate production reporting (Gaylard, Randolph, & Wortley, 2014). Smelters are not spared from these changes. However, their unique situation in the mining value chain set them as strategic targets for upgrading projects. They usually have a longer lifespan than concentrators thereby offering an extended lifecycle to justify investments. Furthermore, numerous smelters have toll agreements with third parties. Accurate cost and production accounting is, therefore, a vital piece of information to fix acceptable contract conditions. Mining companies are ultimately aiming at a clearer view of the operating performance of each business unit to improve their business decisions in a competitive environment. This sought for increase in visibility through plant performance can only be achieved through an upgrade of the metal accounting system. Figure 1 shows the different components of a state of the art system (Gaylard, Morrison, Randolph, Wortley, & Beck, 2009)."

Jan 1, 2017

By A. O. Dufresne

Introductory At the Annual Meeting of the Institute, held two years ago, I had the privilege of presenting a paper on Recent Mineral Discoveries in Western Quebec. In it were pointed out the areas favourable for prospecting in that section of Quebec adjoining the mining camps of northern Ontario; the discoveries that ?had been made were recorded; and some of the developments up to that date were reviewed. Since then, two full years have elapsed, during which a considerable amount of serious work has been performed with such results that western Quebec has today six properties about ready to mine commercial ores of gold, copper, and zinc. These results have been brought about after large sums of money had been invested to bring the district to a producing stage. A smelter has been built, and is already producing copper; two railways have extended their lines into Rouyn; and the Provincial Government has shown faith in the future of the district and has spent large sums of money in the building of highways and for other public works. The purpose of the present paper is to review the developments of the last two years, and the work that has been performed in various spheres of activity in that section on western Quebec covering the county of Abitibi and the northern part of the county of Temiscamingue.

Jan 1, 1928